Retained rights - Non EEA family member - questions about how to apply

[Lecy]

Hello all,
Can you help with some questions? I read evething I could and I’m still confused.
I’ve been married for 4y to a Portuguese citizen.
He came to London in March 2017 and I came in May 2017, so 1y and 3 months ago. I have family member valid until 2022. He worked all this time with permanent contract and I‘ve been working since october 2017 in a restaurant. We have no children.
Now we broke up and we’ll sign the divorce soon.
I read that I can apply for Retained Rights of residence and, for now, he agreed to give me all documents I need for this. My questions:

Do you think I’m qualified for retained rights of residence?

After divorce, do I need to apply immediately?
(I need to go to my country in December and I’m afraid there is not enough time to get divorced and apply and get my passaport back until there)

Which form do I have to fill? Is it the same as family permit process?

Do you think the fact that I work without a permanent contract, with weekly payments, can be bad to prove my treat rights here?

I really appreciate if someone could help me!
Thank you all